Image processing apparatus and image processing method for dynamic thumbnail generation of omnidirectional image

1. An image processing apparatus comprising: a processor executing computer instructions that cause the processor to operate as: a display control unit configured to display a partial region of an omnidirectional image on a first screen; a changing unit configured to change the partial region of the omnidirectional image to be displayed on the first screen in response to a user's operation; a measurement unit configured to measure time during which each of partial regions of the omnidirectional image is displayed on the first screen; a generating unit configured to generate a thumbnail image from the omnidirectional image based on an angle-of-view information; and an electronic memory, configured to store the angle-of-view information representing a position of the partial region of the omnidirectional image which is displayed on the first screen and associating with the measurement time longer than a threshold time, wherein the electronic memory stores the angle-of-view information representing the position, at which the partial region of the omnidirectional image is lastly displayed on the first screen, among positions of partial regions of the omnidirectional image each of which is displayed on the first screen longer than the threshold time, and wherein the display control unit is further configured to display, on a second screen which is different from the first screen, the thumbnail image corresponding to the stored angle-of-view information representing the omnidirectional image.

2. The image processing apparatus according to claim 1 , wherein the generating unit generates the thumbnail image after displaying the partial region of the omnidirectional image on the first screen is finished.

3. The image processing apparatus according to claim 1 , wherein the omnidirectional image is an omnidirectional image generated by combining together a plurality of images obtained by a plurality of imaging devices.

4. The image processing apparatus according to claim 1 , wherein the display control unit displays the partial region of the omnidirectional image corresponding to the angle-of-view information, on the first screen, before receiving the user's operation, when the angle-of-view information is stored.

5. An image processing method comprising: displaying a partial region of an omnidirectional a image on a first screen; changing the partial region of the omnidirectional image to be displayed on the first screen in response to a user's operation; measuring time during which each of partial regions of the omnidirectional image is displayed on the first screen; storing angle-of-view information representing a position of the partial region of the omnidirectional image which is displayed on the first screen and associating with the measurement time longer than a threshold time; generating a thumbnail image from the omnidirectional image based on the angle-of-view information; and displaying, on a second screen which is different from the first screen, the thumbnail image corresponding to the stored angle-of-view information representing the omnidirectional image, wherein the angle-of-view information represents the position, at which the partial region of the omnidirectional image is lastly displayed on the first screen, among positions of partial regions of the omnidirectional image each of which is displayed on the first screen longer than the threshold time.

6. A non-transitory computer readable medium that stores a program configured to be executed by a computer, the program including instructions for: displaying a partial region of an omnidirectional a image on a first screen; changing the partial region of the omnidirectional image to be displayed on the first screen in response to a user's operation; measuring time during which each of partial regions of the omnidirectional image is displayed on the first screen; storing angle-of-view information representing a position of the partial region of the omnidirectional image which is displayed on the first screen and associating with the measurement time longer than a threshold time; generating a thumbnail image from the omnidirectional image based on the angle-of-view information; and displaying, on a second screen which is different from the first screen, the thumbnail image corresponding to the stored angle-of-view information representing the omnidirectional image, wherein the angle-of-view information represents the position, at which the partial region of the omnidirectional image is lastly displayed on the first screen, among positions of partial regions of the omnidirectional image each of which is displayed on the first screen longer than the threshold time.